Elastic wraps are primarily used to wrap injuries. When correctly placed, elastic wraps impart support to strained tendons ligaments or muscles and/or apply continuous pressure to lacerations to reduce bleeding. Some of the most effective wraps exhibit both stretch and elasticity. Stretch is important to ensure that movement of a wrapped limb or joint is not unduly restricted by a wrap and also to ensure that blood flow to the affected area is not restricted. Elasticity ensures that the wraps return to their initial shape after being stretched by the patient in order to provide continuing support to the wrapped injury.
Elastic wraps are increasingly used in industries where injuries are quite prevalent. Examples of such industries include the meat packing industry and professional athletics. The private sector also uses elastic wraps for injuries incurred during recreational activities. When the wraps are used in the private sector or in industry, the injured individual commonly will apply the wrap to the injury without assistance from another person. Ideally, dispensing elastic wraps would not require assistance from another person.
Elastic wraps are commonly sold in strips in roll form. Rolling condenses the strips and also eases dispensing of the wrap without risk of tangling the wrap. In order to dispense elastic wrap, the desired length of elastic wrap is unrolled by unwinding the desired length. The wrap is then cut with a pair of scissors or similar cutting instrument. This method of dispensing is quite cumbersome and very difficult if an injured person must dress her own injury.
Ideally, a cutting instrument would not be required to sever the wraps at the appropriate length. However, due to the construction of elastic wraps, a cutting instrument such as a scissors is usually required to cut the wrap.
Elastomeric wraps are known in the art and are described in U.S. Pat. Nos. 5,230,701, 3,575,782, 4,366,814, and 4,984,584, the disclosure of which are hereby incorporated by reference. The wraps are formed of varied materials including but not limited to nonwoven fabrics, films and foams.
Many wraps are comprised of unoriented nonwoven fabrics. The random orientation of fibers of these fabrics provides useful properties and characteristics. One of these characteristics is the ability of such fabrics to resist continued linear tearing in the cross direction after introduction of an initial tear in the fabric. While this resistance-to-split characteristic of nonwoven fabrics is a beneficial attribute for various applications, it presents certain difficulties when nonwoven fabrics are used for wraps dispensed from a roll because a cutting instrument such as a scissors is necessary to dispense the fabric. Beyond the properties of the fabrics used to manufacture wraps, the fact that the wraps are elastic make the wraps exceedingly difficult to tear. When one attempts to tear an elastic wrap, the elastic wrap is stretched rather than torn due to the resiliency of the wrap. If one does succeed in tearing an elastic wrap, the resulting tear is usually uneven. Due to the difficulty in tearing elastic wraps and the resulting nonlinear tears if the wrap is torn, a tearable elastic wrap is needed.
One approach to providing a tearable nonwoven web is disclosed in Greenway, U.S. Pat. No. 4,772,499. Greenway suggests applying binder to the nonwoven web in spaced linear bands so that the web can be torn in a linear fashion along the binder-free bands of web. Unfortunately, the cost of producing such a banded nonwoven web is prohibitive for many purposes and differences in the surface characteristics of the web as between the binder-free and binder-containing bands would significantly complicate manufacture of the web. It is also perceived that such bands would detract from the performance of the tape.
Patent Cooperation Treaty Publication WO 93/15245 filed by the Minnesota Mining and Manufacturing Company of St. Paul, Minn. discloses an embossed nonwoven tape including both staple and binder fibers. The specific composition of the tape in combination with the embossed pattern on the tape renders the tape tearable in the cross-machine direction along an embossed pattern in the tape. The tearable tapes disclosed by this publication are limited to those which include a significant proportion of melt-activated binder fibers.
A need exists for elastic wraps in roll form which can be dispensed without the need for scissors or other cutting tools and which tear cleanly and evenly.